Abstract

International audience; We present in this paper the concept of solar hybrid road and the numerical model studied and develop to compute its thermal state at any time step. The aim of these new structures is to collect part of the solar radiation during the summer period, to prevent from icing at the surface during the winter period. As it is reversible, it will help also to prevent from a too high structure temperature (in particular closed to the surface) in summer season. Two types of modifications, compared to traditional structures are presented. The first one concerns the insertion of a porous layer allowing a heat fluid to exchange thermal energy. The second one concerns the use of a semi-transparent material at pavement surface allowing the solar radiation to penetrate deeper in the structure. The numerical model of this multi-physics problem develop with the finite element method is presented and discussed. A validation on two test cases is proposed. First results on energy harvesting evaluation for few locations (i.e. climatic conditions) in France are presented and discussed. Finally, conclusion and perspectives are proposed. Document type: Conference object

Abstract

Modeling a rotor blade flow field involves computing the blade motion, elastic deformation, and the three-dimensional forces and moments for specific trim conditions. Such a complex multiphysics problem, which includes a strong fluid-structure interaction, should be modeled by coupling separate solvers which are specialized on solving single-physics problems. In this work, we present a modular and extensible TAU-CAMRAD II coupling environment using the preCICE coupling library [1]. In this coupling, the aerodynamic forces and moments were computed with the CFD solver TAU. The blade control angle for the CFD simulation were determined by the CSD solver CAMRAD II. We validated the implementation using a modified model of the HART-II rotor at an advancing ratio of µ=0.3. Besides the potential that this work unlocks for future simulations of an active rotor, it also serves as an example of using preCICE for geometric multi-scale (1D-3D) coupling of closed-source solvers for periodic phenomena.

Abstract

The simulation of an oleo-pneumatic shock absorber is discussed focusing on the solver validation and high fidelity case setup. The multi-physics nature of the problem is tackled by conducting a range of validation cases in the base areas expected to be of relevance. A dynamic system model of the shock absorber is used to generate physically consistent boundary conditions. In addition, steady RANS simulations provide a preliminary insight into the internal flow development and to assist in the design of higher resolution grids.

Abstract

Particle clusters form in the turbulent flow of boilers and furnaces when injecting pulverized coal. We study the difference in conversion behavior between a pul verized coal cluster and a single char particle. The simulations are done using a detailed particle model in OpenFOAM.The detailed particle model is capable of spatially resolv ing char particles and solving transport equations for heat and mass inside the particles. Furthermore, a surface chemistry model is employed for modeling gas-solid reactions in side the pores of the particles. The char particles are coupled to the surrounding bulk fluid phase using explicit Robert-Neuman coupling. 2-D simulations are carried out for a cluster of 16 particles and a single particle. Both simulations use the same initial con ditions, boundary conditions and particle properties. The results indicate that a lack of oxygen penetration toward the center of the particle cluster alters the thermo-chemical conversion behavior when compared to the single particle. On average this leads to a decrease of the thermo-chemical conversion rates for particles in the cluster, resulting in a reduction of solid carbon consumption compared to the same number of single particles.